Unformatted text preview: diFerence in performance to the signal constellations of the two schemes. Problem 3 (Pulse shaping in MPAM) Assume that the pulse ψ ( t ) of a MPAM communication systems is no longer con±ned to have its support in [0 , T ), where T denotes the signalling interval, i.e., that its time duration is greater than T . 1. Specify the condition that ψ ( t ) has to satisfy such that there is no intersymbol interference (ISI); i.e., such that the output Y n of the demodulator depends (still) only on the transmitted modulation symbol X n , and not on previous or following symbols. (A bit tricky.) 2. Derive the above condition in the frequency domain (Nyquist criterion). (Again a bit tricky.) B²l, TPe. Digital Modulation 1 NavCom...
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- Spring '10
- Pulse shaping, Digital modulation, modulation symbol Xn